A set of stock options granted in 2001 were converted to shares by the company in 2003, held by a trustee in Germany. We employees never paid a dime, and never received any tax statements. In 2012, a very large company offered to buy out the shareholders of the smaller company to acquire controlling interest. The trustee was reimbursed €1 for each share, and employees were paid €6.1 for each share. Still no statements, no tax forms, nothing except the offering documents and the EFT back in May (not even a paper check).

What should have happened, and when? What is the employee's obligations to report in the absence of reporting by the employer, trustee in Germany, acquiring company, etc.?

Is there a difference between reporting this as a stock sale versus treating it as an ISO? (Was it really an ISO?) What dollar amounts should be reported, if any?